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A series of samarium (Sm) doped hydroxyapatites containing strontium (Sr) with controllable and adjustable luminescence were designed and prepared via chemical hydrolysis co-precipitation method. The effects of doping concentration of Sm on the structure, composition, photoluminescence (PL), energy transfer, substitute site, fluoresce lifetime and luminescence color of samples were investigated. It is shown that the introduction of Sr ions induces the structure and composition change for Sm doped samples. The typical transitions of Sm3+ at 564, 601, 648 and 707 nm due to 4G5/2→6HJ/2 (J = 5, 7, 9 and 11) transition under the excitation of 404 nm were detected. The PL intensity is affected by the Sr/Ca ratio and Sm concentration, and the optimal concentration of Sm is 0.8 mol% when Sr/Ca ratio equals 7/3. The non-radiative transitions and energy transfer of Sm ions are the main reason for the quenching, and the interactions among ions are ascribed to dipole–dipole type by theoretical calculation. Besides, the ratio of PL intensity between 601 and 648 nm (rO/R = I601 nm/I648 nm) indicates the symmetry and substitution process of Sm ions to Ca/Sr ions. The fluorescence lifetime (τ) decreases with the concentration of Sm increasing, which is the result of the decrease of distance and the enhanced interaction between Sm ions. The CIE chromaticity coordinates and luminescence color of samples are in the orange-red region and have close relation with the concentration of Sm. Furthermore, the cytotoxicity evaluation and confocal laser scanning microscopy (CLSM) observation of samples via cells indicate the good biocompatibility and safe use of this kind of bio-based luminescent materials for their potential efficient fluorescence labeling and detection.

Rechargeable Li-CO2 batteries (LCBs) are considered as a promising candidate for the next generation energy storage system, but still be impeded by the lack of high-performance cathode catalyst and poor understanding for the complicated reaction mechanism. In the present work, we demonstrate that the catalytic capability of cathode catalyst of LCBs can be remarkably enhanced from the accelerated reaction kinetics using a p-type substrate as adsorption/desorption promoter for refined reaction route. A carbon-free atomic Ir-Te cathode catalyst with Ir atomic cluster is uniformly super-assembled on the surface of Te nanowires forming an amorphous surface layer (ca. 3 nm) to maximize the catalytic capability of active Ir sites and provide a refined reaction pathway due to synergistic effect of Ir active sites and Te substrate. The adsorption ability of Li2C2O4 during discharging and the desorption ability of CO2 species during charging of the p-type Te substrate could both promote the catalytic reaction kinetics and optimize the reaction pathways on Ir active sites. Finally, a large specific capacity of 13,247.1 mAh g−1 and an excellent high rate cyclability with stably over 350 and 200 cycles at the current density of 1000 and 2000 mA g−1 are achieved. This contribution provides a rational design strategy for high performance cathode catalyst, and intrinsic insight towards the understanding the reaction mechanisms of LCBs.

The inferior energy density limits the practical application and sustainable development of supercapacitors. Excellent electrode materials can effectively improve the specific capacitance and operating potential window. Thus, we deposit brush-like nickel ferrite (NiFe2O4) nanosheets and CuCo2O4/CuO nanowire arrays to construct a binder-free electrode with tree-like CuCo2O4/CuO/NiFe2O4 arrays. The resulting CuCo2O4/CuO/NiFe2O4 electrode shows an outstanding specific capacitance (2067 F/g) and wide potential window (−0.1-0.6 V). The contribution rate of surface faradaic redox reaction is calculated to be 71% at 1 mV/s and assembled CuCo2O4/CuO/NiFe2O4//AC device realizes a remarkable energy density (77.1 Wh/kg at power density of 851.4 W/kg) and cyclic performance (92.9% of initial specific capacitance retained after 10,000 cycles). Apparently, the CuCo2O4/CuO/NiFe2O4 electrode as a novel binder-free electrode has great application potential and our work offers a novel idea to construct the arrays of multicomponent composite materials.

Physical adsorption is a common method to solve the contamination of methylene blue in dyeing wastewater. As a kind of adsorption material, cellulose aerogels with high porosity and surface areas have great potential application in methylene blue removal. However, the week hydrogen bonding between cellulose nanofibers making the cellulose aerogels with the poor mechanical properties and can be easily destroyed during adsorption. Hence, the preparation of cellulose aerogels with high mechanical strength is still a great challenge. Here, we report a robust super-assembly strategy to fabricate cellulose aerogels by combining cellulose nanofibers with PVA and M-K10. The resulting cellulose aerogels not only has a robust chemically cross-linked network, but also has strong H-bonds, which greatly enhance the mechanical properties. The resulting cellulose aerogels possess a low density of 19.32 mg/cm3. Furthermore, the cellulose aerogel shows 93% shape recovery under 60% strain (9.5 kPa under 60% strain) after 100 cycles, showing excellent mechanical property. The adsorption capacity of cellulose aerogel to methylene blue solution of 20 mg/L is 2.28 mg/g and the adsorption kinetics and adsorption isotherms have also been studied. Pseudo-second-order kinetic model and Freundlich isotherm model are more acceptable for indicating the adsorption process of methylene blue on the cellulose aerogel. Thus, this compressible and durable cellulose aerogel is a very prospective material for dyeing wastewater cleanup.

Lithium metal (Li) is regarded as the “holy grail” in the anode material of next-generation high-energy-density batteries. However, the Li dendrites and “dead Li” produced during cycling limit its commercialization process. A properly designed three-dimensional (3D) skeleton plays an important role in determining the performance of Li metal anodes (LMA). Herein, we develop a super-assembled surface-modified lipophilic thin ZnO layer by atomic layer deposition (ALD) and multi-level Cu nanofibers (MCN) on a Cu foam (ZnO-MCNCF) as an advanced Li metal anode host. During the Li plating process, lipophilic ZnO layer can induce uniform nucleation of Li. Meanwhile, the unique hierarchical structure provides a larger specific surface area to distribute the surface charge uniformly, adjust the current density, and ensure more uniform Li deposition. Consequently, the as-designed ZnO-MCNCF host enables dendrite-free deposition of Li, high coulombic efficiency, and remarkable cycling stability at various current densities. Compared with CF and MCNCF host, ZnO-MCNCF has significantly improved Li plating/stripping behavior, with high coulombic efficiency (CE) and excellent Li dendrite growth inhibition ability. The Li@ZnO-MCNCF electrode can be operated for 1400 h at a current density of 10 mA cm−2 and large area specific capacity of 10 mAh cm−2 with an ultra-low overpotential (57.1 mV) without significant fluctuations. The LiFePO4-Li (LFP-Li) and LiCoO2-Li (LCO-Li) full cells also exhibit superior cycling and rate performance.

To explore the role of induction chemotherapy (IC) followed by concurrent chemoradiotherapy (CCRT) versus CCRT alone in patients diagnosed with N3 nasopharyngeal carcinoma (NPC).A total of 787 patients with newly diagnosed N3 NPC treated with IC + CCRT or CCRT alone were included. Progression-free survival (PFS) was the primary endpoint. We balanced variables using propensity score matching (PSM). Kaplan-Meier curves with log-rank tests were applied to evaluate the survival condition of each group. Independent prognostic factors were identified using the Cox regression analysis.PSM assigned 228 patients to IC + CCRT and CCRT alone groups. Survival analysis for the matched data set showed that IC + CCRT achieved better survival outcomes compared with CCRT alone, and significant difference was observed in 5-year PFS [74.8% (95%CI 69.2 ∼ 80.9%) vs 65.4% (95%CI 59.4 ∼ 72.0%), P = 0.008], 5-year OS [(77.4%(95%CI 71.9 ∼ 83.3%) vs66.3%(95%CI 60.3 ∼ 72.9%), P = 0.005)] and 5-year distant metastasis-free survival (DMFS)[(81.8%(95%CI 76.7 ∼ 87.2%) vs72.4%(95%CI 66.7 ∼ 78.7%), P = 0.007)] between the two treatment groups. In multivariate analysis, IC + CCRT remained an independent protective factor for PFS (adjusted HR, 0.603; 95% CI, 0.433-0.841; P = 0.003), OS (adjusted HR, 0.568; 95% CI, 0.406-0.793; P 0.001), and DMFS (adjusted HR, 0.541; 95% CI, 0.364-0.805; P = 0.002).More chemotherapy should be considered in patients with N3 NPC because of its ability to improve survival time. This could be from the use of IC or adjuvant metronomic chemotherapy.

The stiff film/compliant substrate composite structure with a high modulus ratio finds a wide range of applications in production and in scientific research, and its indentation behavior cannot be described by the traditional theory when the film thickness is reduced from the millimeter scale to the micrometer or nanometer scale. In order to better understand the trans-scale indentation response of the composite structure caused by the reduction in the film thickness, this problem is solved analytically with the strain gradient theory and integral transformation. The gradient effect on the indentation response of the system is assessed in detailed from three aspects: load-displacement relationship, surface topography and distribution of bending moment on the film. In addition, the influences of film thickness, modulus ratio of the film to the substrate, contact radius and Poisson's ratio on the gradient effect are investigated. It is found that the gradient effect on the indentation response of the system, which is not sensitive to the contact radius and Poisson's ratio, is related not only to the film thickness but also to the modulus ratio of the film to the substrate. Based on the above analysis, a dimensionless number (g/l) is proposed to evaluate the gradient effect on the indentation behaviors of the system. And with the help of the dimensionless number, a new simple and accurate method for measuring the material length scale is proposed. Our research provides a theoretical basis for an in-depth understanding of the gradient effects on the indentation response of the stiff film/compliant substrate system and for the measurement of the material length scale.

Aim Serum anti-phospholipase A2 receptor (anti-PLA2R) antibodies are highly accurate in diagnosing idiopathic membranous nephropathy (IMN) in populations with kidney disease. However, the diagnostic value of anti-PLA2R antibodies for IMN in diabetic kidney disease (DKD) is unclear. The objective of this study is to determine the diagnostic efficacy and the optimal cut-off value of this marker in populations with DKD. Methods This study included 227 patients with type 2 diabetes who were admitted to the Department of Nephrology of the Chinese People’s Liberation Army General Hospital from May 2016 to January 2018 and underwent pathological diagnosis by renal biopsy. Anti-PLA2R antibodies were detected by enzyme-linked immunosorbent assay in this population. According to the pathological results, the participants were divided into an IMN group and non-membranous nephropathy (non-MN) group. The clinical characteristics were analyzed, the diagnostic ability of anti-PLA2R antibodies was evaluated, and the receiver operating characteristic (ROC) curve was constructed to obtain the optimal cut-off value. Results There were 45 patients in the IMN group, accounting for 19.8% of the study sample. The patients in this group were older at the time of renal biopsy than the non-MN group and presented a shorter duration of diabetes, better glycemic control, lower blood pressure and uric acid, and better renal function; in addition, their clinical symptoms indicated nephrotic syndrome. The optimal cut-off value for anti-PLA2R antibodies for the diagnosis of IMN in DKD was 2.71 Ru/ml, sensitivity was 0.800, specificity was 0.951, positive predictive value was 0.800, negative predictive value was 0.951, accuracy was 0.921, and the Yoden index was 0.750. The area under the ROC curve was 0.87 (95% CI, 0.788–0.952) (p Conclusions Patients in the IMN group were older, had better renal function and general condition, and the clinical symptoms indicated nephrotic syndrome. Anti-PLA2R antibodies had a good diagnostic performance for IMN in the population with DKD, and the optimal cut-off value was 2.71.

The hydrogels with injectable and self-healing properties were prepared from xanthan gum (XG) and silk fibroin (SF) by using sodium trimetaphosphate (STMP) as crosslinker. A three-stage model of oscillation-shear-oscillation experiment was designed to mimic injection process and to observe destruction and regeneration of the hydrogels after shear. The XG3-SF-STMP hydrogels immediately recovered to original storage modulus of 80.6%–93.8% on removing shear. The hydrogels were 3D printed into the self-supporting constructions of hydrogel fibers with connected porous structures, and the XG3-SF-STMP hydrogel fibers exhibited smaller width than XG3-STMP. Oscillation rheological behavior indicated that XG3-SF-STMP hydrogels formed rapidly and exhibited more solid-like gel behavior than XG3-STMP. The hydrogel structures were destroyed under a strain (100%) larger than critical strain, but were rebuilt under a small strain (1%) with recovery ratio of 91.36–93.96% within 120 s, suggesting a self-healing property. Introduction of SF particles into XG3-STMP crosslinked networks improved stiffness and retained recoverability. Carboxyl and phosphate groups in the hydrogel networks are beneficial for XG3-SF-STMP hydrogels to absorb enough liquid electrolytes, leading to effective ionic conductivity. The ion-conductive hydrogel with injectable, self-healing, controlled release and non-cytotoxic properties possesses a promising prospect for tissue engineering and drug release application.

Organoids are considered a game-changing paradigm of research models for human physiology and disease, which provides unsurpassed opportunities across disciplines in basic medical research, drug development, and personalized medicine. Here, we made a deep investigation for global patents of organoid technologies in the past decade using bibliometric analysis for the first time. We have identified a total of 672 patents related to organoid technology. The number of annual patent applications exhibits an overall upward growth trend over the past decade, especially entering an exponential growth since 2015. Notably, 76.64% of patents are related to the construction of organoid models. Liver, brain, and intestinal models take up the first three places in the physiological models, while tumor models account for 76.30% of the total patents for disease models. Furthermore, drug screening is the most preferred application, revealing the great commercial value of organoid technologies in precision medicine and preclinical drug screening.

A thermoregulated phase-transfer Pd nanocatalyst was explored firstly and shown to be highly efficient and recyclable in the atmospheric hydrogenation of α, β-unsaturated ketones. Under optimized reaction conditions, the conversion of chalcone and the selectivity of dihydrochalcone were 99% and 98%, respectively. The catalyst can be easily separated from the product and used directly for four times without evident loss in activity and selectivity. The turnover frequency (TOF) for the atmospheric hydrogenation of chalcone was 870 h−1, which to the best of our knowledge was the highest value ever reported among transition metal nanocatalysts.

We have designed an aqueous gel electrolyte containing fumed silica as the thixotropic gelling agent and poly(ethylene glycol) (MW = 300 g·mol−1) as the non-thixotropic gelling agent. Poly(ethylene glycol) is also the dendrite suppressor and the corrosion inhibitor. Both PEG300 and fumed silica can inhibit dendrite formation, shown by chronoamperometry results and ex-situ scanning electron microscopy images. Furthermore, the corrosion current density on the Zn anode in the 4 wt%FS-1 wt%PEG300 gel electrolyte is 27% less than that of the Zn in the reference aqueous electrolyte. Secondary Zn/LiMn2O4 batteries using the 4 wt%FS-1 wt%PEG300 gel electrolyte exhibit higher cyclability (12% and 39% higher capacity retention, after 300 and 1000 cycles, in Swagelok and large cells, respectively) than those using the reference aqueous electrolyte. The vast improvements in cycling performance, reliability, and higher resistance to premature failure makes the PEG-FS gel a much better alternative to liquid electrolytes for maintenance-free energy storage applications.

Two-dimensional (2D) materials have received extensive attention due to their excellent physical and chemical properties, whose mechanical properties play critical roles in their applications. In this paper, a new convenient method for measuring the modulus of nanofilm by indentation on hard film/soft substrate system is proposed. In order to verify the correctness of the new method, the graphene oxide (GO) nanofilm deposited on polydimethylsiloxane (PDMS) is tested. The modulus of the GO nanofilm is measured as 60.39 ± 7.82 GPa, which is consistent with the modulus measured by previous researches. Finally, the finite element method (FEM) is used to investigate the effectiveness of the new method and to evaluate its error sensitivity to the indenter size, film radius, and the surface roughness. The results show that this method can accurately measure the modulus of nanofilm through the indentation response of the hard film/soft substrate system. Compared with the free-standing indentation test, the method proposed by us eliminates the disadvantages of boundary adhesion and has the advantages of simple sample preparation, easy operation, and high success rate.

A porous zinc anode is successfully fabricated using a simple, scalable method for use in Rechargeable Hybrid Aqueous Battery (ReHAB) systems. The porous anode provides a higher surface area (2X), roughness, and wettability than the planar one. These properties allow for better contact between the anode surface and the electrolyte, increasing the cycling performance when used in the ReHAB system. ReHABs with the porous anode show an improvement in initial discharge capacity (34%) at 1C, capacity retention after 300 cycles at 1C, rate performance at various C-rates, and float charge current (a 94% decrease). This decrease in float charge current corresponds to the lower levels of gas generated from detrimental side reactions during battery operation. The enhancements in the rate performance as well as minimized gas evolution in both small (1.13 cm2 in 1.15 mAh coin-cell) and large (9 cm2 in 7 mAh big battery) show the promising potential of the porous anode for use in large-scale battery applications. Based on the findings from various characterization techniques, suppression in dendrite growth and side reactions on the porous anode surface during battery operations have been the main reason for the improvement in ReHAB cycling performance.

The use of thixotropic gel electrolytes in the rechargeable hybrid aqueous battery improves the battery performance but it is required to have a corrosion inhibitor in the gel electrolyte. These inhibitors are not always friendly to the environment. In this work, we use lignin – a renewable material – to neutralize strong acid sites of the fumed silica gelling agent prior to gel preparation. Linear polarization, chronoamperometry, and ex-situ scanning electron microscopy examinations show that the new gel electrolyte reduces the corrosion on zinc (up to 43%) and supports planar zinc deposit. In other words, the shape of the zinc surface is controlled and it is further confirmed by the XRD and SEM of post-battery run anodes. Moreover, the battery using this new lignin coated fumed silica based gel electrolyte exhibits a float charge current as low as 0.0025 mA after 24 h of monitoring, which is 30.6% lower than the reference. The capacity retention of gelled battery is as high as 82% after 1000 cycles at 4 C, which is 14% higher than the reference battery using reference liquid electrolyte under the same CC-CV test, complemented by lower self-discharge and higher rate capability. The results lead the team nearer to a commercializable gelled battery system.

SnO2 is an appealing anode material for lithium ion batteries. Advantages of SnO2 includes relatively low charge-discharge plateau and highly abundance in nature. However, the volume change (300%) is significant and critically impeding its cycle life. In this manuscript, we address these problems by exploiting an in-situ redox process to prepare graphene encapsulated SnO2 nanoparticles using soluble Sn2+ as the Sn precursor, which is oxidized to SnO2 by using graphene oxide. This method affords graphene @ SnO2 via oxygen bridging through of SnO2 nanoparticles. Furthermore, this method incorporates Fe atom into the SnO2 structure in-situ to create FexSn1-xO2 structure, which exhibits higher Li storage capacity. Our synthetic approach delivers graphene encapsulated FexSn1-xO2 structure, which is located on flexible carbonaceous fibers, and the whole system can be applied as lithium-ion batteries anode without any need of a current collector or binder polymer. This novel Sn based electrode could deliver a high capacity (calculate total electrode mass) of 454.3 mAh g−1 after 200 cycles at 100 mA g−1 (65.1% retention). Unlike most contemporary technologies, increasing the thickness of our Sn based electrode simply increases the capacity proportionally. The areal capacity is 1348.3 μAh cm−2, and it is simply doubled to 2856.1 μAh cm−2 while we double the thickness of electrode.

In this paper, we investigate the instability in a self-exciting regime-switching autoregressive model that is locally stable in each of its regimes respectively. It turns out that the stability locally in each of the regimes is not sufficient to guarantee the stability of the model. The mechanism of the instability is explained and a sufficient condition for the instability is provided.